Quiet New Particle Formation in the Atmosphere

Frontiers in Environmental Science, Journal Year: 2022, Volume and Issue: 10

Published: June 30, 2022

Atmospheric new particle formation (NPF) has been observed to take place in practice all around the world. In continental locations, typically about 10–40% of days are so-called NPF event characterized by a clear and growth that continue for several hours, occurring mostly during daytime. The other either non-event days, or which it is difficult decide whether had occurred not. Using measurement data from locations (Hyytiälä, Järvselja, near-city background city center Budapest), we were able show tends occur also on traditionally as days. One explanation instrument sensitivity towards low number concentrations sub-10 nm range, usually limits our capability detect such events. We found rates at 6 2–20% those traditional Growth newly formed particles very similar between This previously overlooked phenomenon, termed quiet NPF, contributes significantly production secondary atmosphere.

Language: Английский

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Atmospheric nanoparticle growth

Reviews of Modern Physics, Journal Year: 2023, Volume and Issue: 95(4)

Published: Nov. 9, 2023

Atmospheric nanoparticles can serve as nuclei for cloud droplets, thereby inducing significant but uncertain effects on the radiative forcing of climate system. This article focuses physicochemical processes that govern growth these particles from formation molecular clusters until reach sizes where they act condensation nuclei. The review describes latest developments in measurement and modeling connects domains to large-scale simulations such Earth system models. authors recommend closer coordination among laboratory studies, atmospheric measurements, understand importance

Language: Английский

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Opinion: A paradigm shift in investigating the general characteristics of atmospheric new particle formation using field observations

Aerosol Research, Journal Year: 2024, Volume and Issue: 2(1), P. 49 - 58

Published: March 27, 2024

Abstract. Atmospheric new particle formation (NPF) and associated production of secondary particulate matter dominate aerosol number concentrations submicron mass loadings in many environments globally. Our recent investigations show that atmospheric NPF produces a significant amount particles on days when no clear event has been observed/identified. Furthermore, it observed different all around the world growth rates nucleation mode vary little, usually much less than measured condensable vapors. It also local clustering, which cases acts as starting point regional (NPF), can be described with intermediate ions at smallest sizes. These observations, together recently developed ranking method, lead us to propose paradigm shift investigations. In this opinion paper, we will summarize traditional approach describing describe an alternative covering both initial growth. The opportunities remaining challenges offered by are discussed.

Language: Английский

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Road Traffic Emissions Lead to Much Enhanced New Particle Formation through Increased Growth Rates

Environmental Science & Technology, Journal Year: 2024, Volume and Issue: 58(24), P. 10664 - 10674

Published: June 8, 2024

New particle formation (NPF) is a major source of atmospheric aerosol particles, including cloud condensation nuclei (CCN), by number globally. Previous research has highlighted that NPF less frequent but more intense at roadsides compared to urban background. Here, we closely examine both background and roadside sites in Central Europe. We show the concentration oxygenated organic molecules (OOMs) greater roadside, OOMs along with sulfuric acid onto new particles sufficient explain growth sites. identify hitherto unreported traffic-related OOM contributing 29% 16% total background, respectively. Critically, this undiscovered an essential component NPF. Without their contribution rates subsequent enhancements survival, >50 nm produced would be reduced factor 21 site. Reductions hydrocarbon emissions from road traffic may thereby reduce numbers CCN counts.

Language: Английский

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Iodine oxoacids and their roles in sub-3 nm particle growth in polluted urban environments

Atmospheric chemistry and physics, Journal Year: 2024, Volume and Issue: 24(3), P. 1873 - 1893

Published: Feb. 12, 2024

Abstract. New particle formation contributes significantly to the number concentration of ultrafine particles (UFPs, d ≤ 100 nm) and has a great impact on human health global climate. Iodine oxoacids (HIOx, including iodic acid, HIO3, iodous HIO2) have been observed in pristine regions proved dominate new (NPF) at some sites. However, knowledge HIOx polluted urban areas is rather limited. Here, we conducted long-term measurements gaseous iodine sulfuric acid Beijing from January 2019 October 2021 also Nanjing March February 2020 investigated contribution UFP both environments. HIO3 highest summer, up 2.85 × 106 2.78 cm−3 Nanjing, respectively, lowest winter by 96 % 75 %, respectively. exhibits more prominent variation than H2SO4 shows clear diurnal pattern sites with daily maximum around noontime, similar atmospheric temperature, solar radiation, ozone (O3) levels. HIO2 same seasonal trend as but overall about an order magnitude lower concentration. Back trajectory analysis suggests that sources for inland species could be mix marine terrestrial origins, having peak emission warm seasons. While growth marginal our results demonstrate enhances survival probability sub-3 nm 40 (median) occasionally NPF events, suggesting are significant contributor UFPs areas. As per-molecule basis, propose sum used estimate inorganic origin atmospheres amount HIOx.

Language: Английский

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Opinion: Influence of the mean free path of air on atmospheric particle growth

Aerosol Research, Journal Year: 2025, Volume and Issue: 3(1), P. 231 - 235

Published: May 5, 2025

Abstract. Recent studies by Tsalikis et al. (2023, 2024) predicted that the mean free path of air (λair) could be significantly smaller than widely used values a factor ∼ 2. Given fundamental importance λair, question whether an overestimation λair would have profound influence on number aerosol processes must answered. Here we assume newly proposed value is accurate and examine its influences our understanding atmospheric aerosols. We show for collision-induced dynamics such as condensation growth particles, collision rate hence are determined effective vapor particle rather λair. Similar to cause overlooked force field in pure elastic models may enhance vapor–particle collisions; however, this enhancement has been accounted previous studies. As result, find does not substantially i.e., it challenge lower troposphere. Other potential involving high excess latent heat uncertainties sub-5 nm size range also addressed.

Language: Английский

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High contribution of new particle formation to ultrafine particles in four seasons in an urban atmosphere in south China

The Science of The Total Environment, Journal Year: 2023, Volume and Issue: 889, P. 164202 - 164202

Published: May 18, 2023

Language: Английский

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Measurement report: Contribution of atmospheric new particle formation to ultrafine particle concentration, cloud condensation nuclei, and radiative forcing – results from 5-year observations in central Europe

Atmospheric chemistry and physics, Journal Year: 2024, Volume and Issue: 24(18), P. 10667 - 10687

Published: Sept. 24, 2024

Abstract. As an important source of sub-micrometer particles, atmospheric new particle formation (NPF) has been observed in various environments. However, most studies provide little more than snapshots the NPF process due to their underlying observations being limited space and time. To obtain statistically relevant evidence on across environments, we investigated characteristics based a 5-year dataset German Ultrafine Aerosol Network (GUAN). The results were also compared with previous studies, aim depict relatively complete picture central Europe. highest occurrence frequency was regional background sites, average about 19 %, followed by urban (15 %), low-mountain-range (7 high Alpine (3 %) sites. annual mean growth rate between 10 25 nm varied from 3.7–4.7 h−1, while same size range 10–25 0.4 2.9 cm−3 s−1. contribution ultrafine particles (UFPs) 13 21 7 % for background, low mountain range, respectively. influence cloud condensation nuclei (CCN) number concentration aerosol extinction coefficient days mountainous areas. These findings underscore importance local environments when assessing potential impact climate models, they emphasize usefulness long-term measurement network understanding variation features influencing factors over scale.

Language: Английский

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Enigma of Urban Gaseous Oxygenated Organic Molecules: Precursor Type, Role of NO_x, and Degree of Oxygenation

Environmental Science & Technology, Journal Year: 2022, Volume and Issue: 57(1), P. 64 - 75

Published: Dec. 14, 2022

Oxidation of volatile organic compounds (VOCs) forms oxygenated molecules (OOMs), which contribute to secondary pollution. Herein, we present measurement results OOMs using chemical ionization mass spectrometry with nitrate as the reagent ion in Shanghai. Compared those forests and laboratory studies, detected at this urban site were relatively lower degree oxygenation. This was attributed high NOx concentrations (∼44 ppb), overall showed a suppression on propagation reactions. As another result, large fraction nitrogenous (75%) observed, further increased 84% under NO/VOC ratio. By applying novel framework OOM categorization supported by VOC measurements, 50 32% aromatic aliphatic precursors, respectively. Furthermore, are more (effective oxygen number, nOeff = 4-6) than ones (nOeff 3-4), can be partly explained difference initiation mechanisms points possible discrimination termination study highlights roles formation areas, well products that might show between VOCs.

Language: Английский

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Measurement report: The 4-year variability and influence of the Winter Olympics and other special events on air quality in urban Beijing during wintertime

Atmospheric chemistry and physics, Journal Year: 2023, Volume and Issue: 23(12), P. 6663 - 6690

Published: June 19, 2023

Abstract. Comprehensive measurements are vital to obtain big enough datasets for better understanding the complex atmosphere and further improving air quality. To investigate 4-year variation of quality influences special events (Beijing Winter Olympics, COVID lockdown Chinese New Year) on it during wintertime in polluted urban air, we conducted comprehensive observations Beijing, China, 1 January–20 February, years from 2019 2022. The mass concentration PM2.5 its composition (organics, nitrate, sulfate, ammonium, chloride black carbon) number size distributions particles (down ∼1 nm) ions, gaseous pollutants (CO, NOx, SO2, O3) condensable vapors (sulfuric acid oxygenated organic molecules), as well meteorological parameters, were simultaneously measured. days before 22 January without any each year selected variability We found that concentrations CO, total molecules (OOMs), PM2.5, organics, carbon sub-3 nm (N1.3−3) showed similar variations, decreasing 2021 then increasing For however, decreased by due significant emission reduction, leading decrease sulfuric particulate sulfate O3 an opposite compared with NOx. Meanwhile, both oxygen nitrogen contents increased year, implying not only oxidation state those compounds increased, but also NOx was involved more efficiently their formation processes. With higher new particle (NPF) frequencies than 2022, lowest background aerosols ambient temperatures 2021, N1.3−3 still 2021. Unlike N1.3−3, ion 0.8–2 2–4 ranges other years. Then, after 4 February chosen explore influence events. non-event within this date range reference period. Due favorable conditions together reductions anthropogenic emissions, there basically no haze Olympics. Therefore, OOMs, accumulation-mode (N100−1000), much lower, while Although reduction COVID, especially enhancement secondary inorganic aerosol formation, unfavorable conditions, caused severe Hence, OOMs all compositions dramatically Influenced condensation sink sunlight, be comparable between Olympics period lower Year. Additionally, almost at same level different periods, indicating had little impact NPF These results provide useful information development targeted pollution control plans.

Language: Английский

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